Here's a diagram for drilling the proper location: http://firstgenfirebird.org/forums/ubbthreads.php?ubb=showflat&Number=205906&page=2
Here's some discussion about the different types: http://firstgenfirebird.org/forums/ubbthreads.php?ubb=showflat&Number=196652
Link to the 5500 Redline: http://www.mfsperformance.com/index.php?main_page=product_info&cPath=3&products_id=4. I like this one because it has dual lamps and is sealed so condensation will not build up on the lens. Also, it's the 5500 redline and shorter streamlined version.
Install guide from Inline tube: http://www.inlinetube.com/articles/Pontiac%20Hood%20Tach%20Install.htm